Data storage and retrieval systems are used to store information provided by one or more host computer systems. Such data storage and retrieval systems receive requests to write information to one or more information storage devices, and requests to retrieve information from those one or more information storage devices. Upon receipt of write request, the system stores information received from a host computer in a data cache. In certain implementations, a copy of that information is also stored in a nonvolatile storage device. Upon receipt of a read request, the system recalls information from the one or more information storage devices and moves that information to the data cache.
Thus, the system is continuously moving information to and from storage devices, and to and from the data cache. One or more communication links interconnect one or more device adapters and the one or more information storage devices.
As the speed at which data is transferred between the device adapters and the storage devices over the one or more communication links, the physical length of those one or more communication links affect the data transfer rate, the data integrity, and the overall system reliability.
What is needed is an apparatus and method to dynamically adjust signal characteristics, such as signal pre-emphasis, for a signal transferred over a communication link based upon, among other things, the physical length of that communication link.